Biology, chapter 1
Crop production and Management
Why do we need food?
- Food is the basic necessity of all living organism.
- Food gives us energy to carry out basic
- body function such as digestion, respiration, excretion etc.
- Food is required for growth, development and body repair
- Food protects our body against diseases.
Define Agriculture?
Agriculture is applied science that deals with mass production of crop plants and animals used for human beings.
What are the other means of food production apart from agriculture??
- Poultry
- Fishing
- Sericulture
Why Crop production is essential?
To fulfil the food requirement of a large population, increased production, proper management and distribution of food is essential
Define crop?
- Plants of same kind grown at one place
- larger scale is called as Crop.
- The product of cultivated plants is called Crop produce.
- Ex: cereals – Wheat, Rice, Maize etc
- Pulses – Gram, peas, bean
Define Horticulture?
- It is branch of agriculture that deals with
- production of vegetables, fruits, ornamental plants
- It is carried on small scale
- Some of Horticultural crops are potato, Tomato, rose, jasmine, cabbage, pears etc.
Difference between Kharif crop and Rabi crops??
Kharif Crops | Rabi crops |
The crops that are sown in rainy season is Kharif Crops | The crops that are sown in winter season is Rabi crops |
It is sown at beginning of monsoon (June/July) | It is sown at beginning of winter season (October/November) |
It is harvested at end of Monsoon (September/October) | It is harvested in March-April |
It depends on monsoon rains for its growth | It does not depend on monsoon rain for its growth |
Ex: Rice, Maize, Soyabeans etc. | Ex: Wheat, Gram, Peas, Mustard etc. |
Define Hydroponics ?
It is a technique of growing plants in a nutrient solution without soil.
Define agricultural practice ??
Agricultural practices are activities in a particular sequence undertaken by farmers over a period of time to cultivate food crop.
What are the various agricultural practices?
- Preparation of soil
- Selection and sowing of seeds
- Replenishment of nutrients in the soil (manuring)
- Irrigation
- Crop protection
- Harvesting
- Storage
What are the main tools used in agriculture??
- Plough
- Ноe
- Cultivator
Define the uses of Plough?
- Plough is used for Tilling, Scraping of soil, Weeding, Manuring etc.
- Plough consists of Ploughshare- Strong triangular Iron Strip
- Plough shaft – long rod of wood
- The other end of plough is attached to beam and it is put on the neck of the bull.
- Ploughshare is curved to turn soil after cutting.
What is use of Hoe?
- A Hoe is used for removing weeds and for loosening the soil.
- It consists of a long rod of Wood/ Iron
- A strong broad, bent plate of Iron is fixed at one end of a long rod that works like a blade.
- At the other end a beam is attached that is placed on the neck of the bull.
What is a Cultivator?
- Tractor driven plough is called Cultivator.
- It saves time and labour.
What is the first step in agricultural practice?
Preparation of soil is the 1st step in the growing crops. It involves
loosening and turning of soil.
Preparation of soil involves 2 steps.
1) Ploughing
2) Levelling.
How Ploughing is done?
- The process of loosening and turning of soil is called Ploughing/ Tilling.
- It is done by using bull or tractor.
Why loosening of soil is important?
- It creates more air spaces because of which roots of crop plants breathe better.
- Loose soil can hold more water for longer duration. So this helps the root to absorb more water
- Loose soil helps roots to penetrate deeply and fix the plants firmly
- Loose soil mixes with manures & fertilisers more easily.
- Loose soil helps to remove weeds easily.
- Loose soil promote growth of useful microbes. These microbes add humus to the soil.
- During ploughing nutrient rich layer above the soil so this will be used by the plants.
Who is Farmer’s friend?
- Earthworms are farmer friends. They turn and loosen the soil.
- Their burrowing action creates channels through which plant roots penetrate soil more easily.
What is levelling?
- After ploughing, land is levelled using a wooden plank or iron leveller.
- Levellers can be driven by animals / tractor.
Why levelling is done?
- To crush the large pieces of soil called Crumbs levelling is done.
- It prevents soil erosion.
- It helps in the uniform distribution of water and manure.
How seeds should be selected?
- Clean healthy disease free seeds should be selected.
- Seeds that are treated with fungicides should be selected → chemicals that kill disease causing fungi.
How seeds should be sowed?
- Sowing of seeds is the process of placing seeds in the soil.
- Seeds have to be sown at right depth, neither too shallow nor too deep.
- At right internals, they should be placed so that they get proper air, sunlight and nutrients.
What are the methods used for the sowing?
- Broadcasting/ manual method
- By Traditional tool
- Seed drill
- Transplantation
What is Broadcasting ?
- Seeds are scattered in the field by throwing them using hands.
- This system is not efficient as seeds are not properly placed and not sown at depth.
What is traditional method of sowing seeds?
- Traditional method has a funnel shape vertical long tubes with sharp ends.
- Seeds are filled in this tubes, sharp end of tube pierce the soil and place the seeds at that place.
How Seed drill works?
- Seed drill has a funnel shaped seed bowl connected to several tubes.
- Seed drill is attached to plough.
- Plough makes the furrows and seeds from seed bowls are released through tubes and deposited in the soil.
Advantages:
- Seeds are sown uniformly at same distance and depths.
- It also ensures that seeds are covered with soil after sowing
- It saves time and labour.
What is Transplantation?
- The process of transferring seedlings from nurseries to fields is known as Transplantation
- Ex: Paddy, Tomato, chilli, onions etc.
What are the advantages of Transplantation?
- It helps in selecting and planting only healthy seedlings
- Spacing is controlled since it is manually planted.
- 3.Plants get sufficient sunlight, nutrients, water from soil.
Why do nutrients need to be replenished?
- Soil only supply nutrients to the plants.
- It is essential for the growth of plants.
- Continuous growing of crops makes the soil deficient in certain nutrients. So soil loses its fertility.
- Hence soil nutrients need to be replenished from time to time.
What are methods used to restore Soil fertility?
There are two methods to restore soil fertility
Natural method
1) Fallowing
2) Crop Rotation.
3) Mixed cropping.
Artificial method
1) Addition of Manure
2) Addition of Fertiliser
3) Green manure
How Fallowing helps in restoring soil fertility?
The land is left uncultivated (fallow) for one or more seasons.
Fallow land regains nutrients by decomposition of plants and animals by action of microbes.
Define Crop rotation, and how is it used to replenish the soil?
- Crop rotation is the method of growing different crops alternatively in the same field.
- Ex: Farmers grow wheat/barley for the 1st year. And for the next season they grow leguminous plants. like pea or soya bean.
- Rhizobium bacteria present in the root nodules of leguminous plants helps to convert the atmospheric nitrogen into nitrates. These nitrates are easily absorbed by the plants
What is Mixed cropping?
- In this method two or more crops are grown together in the same field.
- The crops are selected in such a way that the nutrient requirement of one crop is fulfilled by another.
- Ex: Cotton & Groundnut
- Pea/soya (legumes) with Wheat/ Rice (Cereal crop)
Define Manure ?
Manure is an organic compound obtained by the decomposition of plant and animal waste by the action of microbes.
Define Composting?
- Composting is a biological process in which the microbes decompose the organic matter present in organic waste material to produce manure.
- The organic waste material includes animal excreta, dry leaves, weeds, animal excreta, sewage waste, faecal matter of humans etc.
- Compost does not contain Nitrogen, Phosphorus, Potassium.
Green Manure:
- Some plants Ex: Sun Hemp, Sesbani are grown in field before sowing seeds.
- These plants at the seedling stage are ploughed back into the soil. They decompose and increase the soil fertility.
Define Fertilisers with Ex:
Fertilisers are artificial ones produced in the factories.
They are the chemical substances that is rich in Nitrogen, Phosphorus, Potassium.
- Ammonium Sulphate, Sodium Nitrate – Nitrogenous fertiliser
- Super Phosphate, ammonium phosphate – Phosphatic fertiliser.
- Potash, Potassium Sulphate – Potassic fertiliser
- Nitro phosphate, urea, ammonium phosphate – Complex fertiliser.
1. Fertilisers are easily soluble in water
2. They are easily absorbed by plants and increase the crop yield.
Disadvantages of Fertiliser:
- Fertilisers are washed away from Irrigation & rainfall into nearby ponds, lakes, river causing water pollution.
- Polluted water unfit for human consumption and Kills. the aquatic animals.
- Fertilisers are Non biodegradable and cause soil pollution
Irrigation
Why water is essential for the survival of plants?
- Water is important for growth and development of flowers, fruits, seeds of plants.
- Along with water, minerals, fertilisers are also absorbed by roots.
- Water is essential for seed germination and for carrying out Photosynthesis.
- Water dissolves nutrient that are transported to each part of plant.
- Water protects crops from frost and hot air currents.
Define Irrigation?
The supply of water to the plants at regular intervals through sources other than rain is irrigation.
What are the factors influencing Irrigation ?
The time and frequency of irrigation depends on
- Nature of crop plants
- Soil nature
- Season based Irrigation
Discuss in detail the factors influencing irrigation?
Crop based Irrigation:
some crops require more water, some require less water.
Ex: Rice – Standing water and continuous water supply.
Wheat, cotton = Require less water.
Soil based Irrigations:
Irrigation depends on Nature of the soil.
Sandy soil =frequent irrigation is needed since it has poor water retaining capacity.
Clayey soil = less Irrigation, since it has good water retaining capacity
Season based Irrigation:
Summer season requires higher rate of irrigation, since there is increased rate of evaporation from soil and leaves.
What are the major sources of Irrigation ?
Wells, Tubewells, ponds, lakes, river, dams, tanks and canals.
Distinguish the traditional & Modern methods of Irrigation?
Traditional method | Modern methods |
It is cheaper but less efficient. | It is comparatively expensive but more efficient. |
Animals/Human labour is required | No Humans or animal intervention required. |
Some traditional ways are Moat (Pulley), Chain pump, dhekli, Rahat | Modern method is Drip system, Sprinkler system. |
How drip Irrigation works?
- It is useful in areas where there is little rainfall.
- No water is wasted.
- In this system, there are holes in the pipes. This allows water to fall drop by drop at the position of roots.
How Sprinkler system works?
- In this method, water is sprayed to the plants using sprinklers.
- The perpendicular pipes have rotating nozzles on top caller sprinklers.
- These are joined with main pipeline at regular intervals.
- Pumps are fitted in this system for lifting water.
- When pump is switched “on” water is lifted and allowed to flow through the main pipe under pressure.
- Through the rotating nozzles, water gets sprinkled.
Points to be Noted in Irrigation:
1. During Irrigation, there should be proper availability of water and adequate drainage in irrigated field.
2. Due to waterlogging, air in soil is replaced with water reduces the supply of air in the roots of plants.
This adversely affects the growth of plants.
Define Weeds?
The unwanted plants that grow along with cultivated main plant crop in the field are called Weeds. Example for weeds
- Amaranthus
- Convolvulus
- Chenopodium.
- Cyperus
- Achyranthus
How weeds harm the plants?
- They consume large amount of nutrients, water, sunlight, which is for crop plants.
- Weeds invite pest, they spread crop diseases.
- Some weeds produce toxic substances that are poisonous to animals & humans.
Define Weeding? What are the various methods of weeding?
The process of removing the weeds from crop field is weeding.
Methods of weeding:
1) Mechanical Method.
2) chemical Method
3) Biological Method
Mechanical methods:
- Weeds are pulled through hands or ploughing tools such as Seed drill, hoe, harrow.
- Weeds that appear during growth of crop manually using plants is removed using trowel.
Chemical method :
Weedicides are weed killing chemicals are sprayed on weeds to kill them. Ex:
- 2,4-D (2,4-dichlorphenoxy acetic acid)
- MCPA (2 methyl- 4 chloro-1-phenoxyacetic acid)
- Dalapon, Siziazine
1.Spraying of weedicides may affect the health of farmer.
2.Grains should be washed thoroughly before consumption.
Biological Method:
- Insects / other organism that consume weed plants are introduced in crop fields.
- This is called Biological method.
- Ex: Wedding of Prickly Pear Cactus using Cochineal insects.
What are pest?
Pest are organism that attack and damage crops.
They may be
- Rodents (rats)
- Insects (locust, Weevils)
- Termites.
Pesticides – It kills the pest and their egg without damaging the crops.
Rodenticides – It kills rodents.
Insecticides – It kills insects. Ex: BHC (Gammexane) Malathion, Disyston.
How crops can be protected ?
1. Fencing the field and use stray animals to keep the other animals that damage the field.
2. Birds can be kept away by keeping scarecrow.
Plant diseases:
Plants can be damaged by diseases caused by certain pathogens such as bacteria, fungi, virus. Disease spread through air, soil, insects.
Some plant diseases are
- Rust and smut of wheat (by Fungus)
- Blight of potato (fungus)
- Wilt disease (Bacteria)
Pesticides, bactericides, fungicide, larvicides are also used to protect the plants against the pathogens.
Disadvantages of Pesticides:
- Using huge amounts of pesticides are dangerous to humans and other animals.
- Pesticides mixed with soil, gets dissolved in soil , and these are absorbed by plants.
- Before consuming fruits and vegetables we need to wash them thoroughly with water and then use it.
- This is done to remove the coating of pesticides on the outer surface of fruits and vegetables.
Harvesting:
- The process of cutting and gathering of crops after its maturation is called Harvesting.
- Harvesting is done either by manually by sickle or by harvester machine.
- Some festivals associated with harvest festival are Pongal, Baisakhi, Holi, Diwali,Bihu etc.
Define Threshing?
- After the crop is harvested, grains are separated from the chaff by the process called Threshing.
- This is done either manually by striking the crop against hard surface
- or by using a machine called Thresher.
- Combine Machine: It combines and performs dual functions as a Harvester and Thresher.
Define Winnowing?
- It helps in separation of grains from husk
- Heavier grains fall down while light husk and hay are carried away by the wind.
- Winnowing is also done by winnowing machine.
Storage:
Why it is necessary to store the grains?
- It is necessary for the regular supply food products throughout the year
- If not, they are damaged and wasted by rodents, pests and some microbes.
- In India, 10% of crops produced are spoiled.
Why grains are Sundried?
Harvested crop grains have more moisture content.
So, before storing they are sundried to reduce the moisture content.
Mechanical driers are with hot blowing air are used to dry the seeds. This prevents the attack of insect, pest, bacteria, Fungi.
How the dried grains are stored?
- On a small scale, they are stored in Jute bags / metallic bins.
- On a commercial scale, they are stored in gunny bags in granaries / silos.
How grains are protected in gunny bags?
- Grains filled in gunny bags are stacked in large godown.
- They are kept 60-70cm away from walls on wooden platforms,
- These platforms are 10-15cm above the ground to protect the grains from moisture.
- Pathways are provided between stack grain filled bags for periodic inspection, spraying and fumigation. This is done to protect grains from pest.
What are Silos ?
- Silos are big and tall cylindrical structures.
- They store different stocks of food items at different levels.
- Each level has an opening, through which grains are taken when required.
How are fruits and vegetables stored?
- These are stored in cold storagesthat has temperature between 0°C -4°C.
- Cold storages used to store crops for a long time, reduce loss, spoilage of food, maintain nutritive value.
What is Buffer Stock ?
- The government has built a huge reserve stock of food grains.
- This stock of food grains is called Buffer Stock.
- This is done to ensure the availability of food grains throughout the year and to meet emergency requirements.
- It also maintain price line of food grains in open market.
What is Plant Breeding?
Plant breeding is a technique used to control the reproduction in plants to get the desired offspring.
Define Hybridisation?
- Hybridisation is a technique used for developing new varieties of crops by cross breeding two different varieties.
- New variety contains the desired characteristics of both the parents.
What is Emasculation?
The anthers of the female plant are removed at bud stage to prevent self pollination and this process is called Emasculation
Define Green Revolution ?
- Rapid increase in agricultural production by high yield variety seeds and new technology.
- They imported High yielding varieties of wheat from Mexico.
- Similarly, High yielding varieties of Rice, maize, Bajra, sugarcane were developed by Indian Scientist through cross breeding
Define Organic Farming ?
It is a type of farming method that depends mainly on biofertilisers, biopesticides, manure and healthy cropping system.
Define animal Husbandary ?
The Science that deals with breeding, Feeding and caring of domestic animals is called as Animal Husbandary
Define Poultry farming ?
Rearing and breading of hen, duck, Turkey for egg and meat is Poultry farming.
Define Pisciculture ?
The production of fish on large scale by farming fish in fish nurseries (Hatcheries) is known as Pisciculture.
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